State-of-the-art gas turbines, particularly the heavy-duty gas turbines used to generate a significant percentage of the world's energy supply, require a substantial amount of cooling to stop various components from melting.
An area of particular importance in terms of cooling is the first blade in the turbine of a gas turbine. In addition to being subjected to very high temperatures, the first blade is also subject to high mechanical load due to rotation.
The root of the first blade is a fir tree, and the fir tree is attached to the rotor of the gas turbine. The combination of high temperature and high load tends to limit the lifetime of the fir tree. As a result it has been appreciated that the cooling of the fir tree could usefully be improved.